Heating vessel

ABSTRACT

A furnace having a fireplace surrounded by a substantially cylindrical water boiler shell for burning of liquid or gaseous fuel by means of a burner joining a fireplace, comprising a water boiler shell, a burner disposed at one end of the water boiler shell on the end side of the latter. At least one annular channel is provided and a hood is arranged at one ed of the furnace and feeding off flue-gases from the end of the water boiler shell disposed opposite the burner in axial direction of the furnace through the at least one channel to the other end of the furnace. At least one wall of the annular channel has a plurality of annular- or screw-like indentations and projections and at least one wall of the annular channel engages a water tank connected for water communications with the water boiler shell.

nited States Patent [is] 3,672,337 Ospelt et al. [4 1 June 27, 1972 [541HEATING VESSEL 2,400,352 5/1946 Higley et al ..1 10/97 x Inventors:Gustav 06pm Vaduz, St Johann; wow 2,593,032 4/1952 Johnson 122/156 X 'fTflesen both Llecmen' Primary Examiner-Kenneth W. Sprague s cmAltomeyErnest G. Montague [73] Assignee: Gustav Ospelt Hovalwerk AG,Vaduz, Y

Liechtenstein 5 7] ABSTRACT [22] Filed: Ju|y 1970 A furnace having afireplace surrounded by a substantially cylindrical water boiler shellfor burning of liquid or gaseous PP 52,423 fuel by means of a burnerjoining a fireplace, comprising a water boiler shell, a burner disposedat one end of the water 2 1o 97 Milershe" and side 8 M Sc h 155 A, 156;I 10 97 97 D ranged at one ed of the furnace and feeding off flue-gasesfrom [5 1 le 0 are l l the end of the water boiler shell disposedopposite the burner in axial direction of the furnace through the atleast one chan- [56] Cited nel to the other end of the furnace. At leastone wall of the an- UNlTED STATES PATENTS nular channel has a pluralityof annularor screw-like indentations and projections and at least onewall of the annular chan- 2,684,054 7/1954 Carson 122/156 X I V nelengages a water tank connected for water communications 3,180,322 4/1965Glbbard with the water boiler shell. 2,080,405 5/l937 Hussey 1,640,3l78/1927 Haas et al. l 22/ l 55 X 2 Claims, 5 Drawing Figures PATENTEDJUW1972 saw a nr 2 lm eniors ing the fireplace. These more complicated andexpensive ves-' sel constructions, which require often 'a burner takeninto consideration the furnace construction with a particularly strongblower, are too expensive for normal, smaller heating arrangements, asby example, in one-family homes. Other furnaces of a simpler structureare known, in which the flue-gases, before emerging from the fireplaceby a flue-gas branch, run over or flow about fireplace structuresfeeding furnace water, in order to release as much as possible of heatto the furnace water, by

example, a co-axial tubular helix disposed at a radial distance from thewater boiler shell in the fireplace on the outside and on the inside andflow through the gaps between the individual windings of the tubularhelix. In such furnaces, partly the heat transfer from the flue-gases tothe furnace water, that means the furnace efficiency is notsatisfactory, partly improvement measures for the increase of the heattransfer brought about an increase of the manufacturing costs and of thestream resistance in the furnace. 7

It is one object of the present invention to provide a furnace, whereinthe requirements and desires of the practice, which are not consideredfulfilled with the known furnaces, led to a furnace, which is mostpossibly very economical, in spite of a simplest structural arrangement,which exploits'theheat produced by the burner firing in a most possiblyeconomical and satisfactory manner and prevents thereby strongdeviations of the flue gases'and high stream resistances, so that it canbe operated with any simple and economical, conventional burners,

It is another object of the present invention, to provide a furnace ofthe indicated type which is arranged such, that'the burner is disposedat one end of the furnace at its end side and the flue-gases are guidedfrom the end of the fireplace disposed opposite the burner in axialdirection of the furnace through one or a plurality of annular channelsto the flue-gas outlet disposed at the other end of the fumace' and atleast one wall of each annular channel is equippedwithalternately'successive ring-or screw-like indentations and projectionsand at least one wall of the annular channels defines a water tankcommunicating with a water boiler shell for feeding water therethrough.i

With these and other objects in view, which will become apparent in thefollowing detailed description, the present invention, which is shown byexample only, will be clearly understood in connection with theaccompanying drawings, in which FIGZ' I is an axial section of a firstembodiment of the furnace with an annular channel;

FIG. 2 is an axial section of another embodiment of the furnace of FIG.1;

FIG. 3 is a third embodiment of the furnace designed in accordance withthe present invention;

FIG. 4 is an axial section of a third embodiment of the presentinvention; and I FIG. 5 is a section along the lines V-V of FIG. 4.

Referring now to the drawings and in particular to FIG. '1, this Figureshows a standing furnace, the cylindrical water boiler shell I of whichsurrounds a fireplace 2, in which through the upper end side of thefurnace the burner 3 terminates. From the end of the fireplace 2disposed opposite the burner 3, the flue-gases fiow in axial directionof the furnace through an annular channel 4, which leads to a flue-gasoutlet 5 formed as a collecting chamber and disposed between twocoaxial, cylindrical walls 6 and 7. The outer wall 7 of the annularc'hannel4 limits a water boiler she'll land in the shown exampleconstitutes an extension of the water boiler shell I, downwardly. Theinner wall 6 of the annular channel 4 is equipped with annularorscrew-like waves and consists of a simple drum of sheet material, whichcan be produced comparatively easily and simply and'can have a slightand material Saving wall thickness.

The undulated wall '6 forms jointly with the straight wall 7 an annularchannel, the open cross section of which has in axial direction of thefurnace alternately narrow points and hollow-space-like widenings andcauses thereby, that the fluegases in axial flow of the annular channelare continuously always altemately'compressed and accelerated andrelieved of tension and decelerated, respectively.- By this arrangement,a high heat transfer between the flue-gases and the furnace water isbrought about, so that in spite of a simplest and noncomplica'ted gasconduit between the fireplace and the fluegas output, the flue-gasesrelease to a high degree their heat to the furnace water.

The chamber 9 disposed within the inner wall 6 of the annular channel 4is'closed' in accordance with another feature of the present inventionat its end pointing towards the fireplace by means of a cross wall 10.This cross wall locks in only the path for the flue-gases through thechamber 9, it forms beyond that jointly with the wall 6 a hollow spaceopen only in downward direction to the flue-gas outlet, which hollowspace has the surprising advantage that it operates as a damping chamberand pressure oscillations of the flue-gases, which are caused, byexample, by the burner firing and have disagreeable'audible noises upinto the chimney, are absorbed prior to the exit of the flue-gases fromthe furnace.

In the embodiment disclosed in FIG. 2, the inner wall 6 of the annularchannel 4 equipped with undulations limits a water tank 1 l, whichcommunicates with the water boiler shell 1 for feeding of water. In thiscase, the undulated formation of the wall 6 has the further advantage,that in view of the undulations, it has a high deforming stiffness andmakes possible the use of thinner, expense saving vessels sheet metal.It is to be understood, that on the inner side of the water tank I 1still a second annular channel can be provided, which in turn from theinside can be defined by a simple wall corresponding with the wall 6 inFIG. 1, or by a water tank corresponding with the water tank 11 in FIG.2. In this case, the cross wall 10 covers as a matter of course only thespace surrounded by the inner length wall of the second annular channel.

If an annular channel is provided, as it is shown in connection with theembodiment of FIG. I, and the inner limiting wall of the annular channelis formed with indentations and projections reaching close to the outerlimiting wall and is formed without water cooling, the indentations canbe formed such, that they extend up to the longitudinal axis of thefurnace.

Such embodiment is disclosed in FIG. 3, in which an annular channel 12is formed between the wall 7 limiting the water tank 8 and a pluralityof plate-shaped discs 13, which are disposed crosswise to the axialdirection of the furnace and are arranged spaced apart from each otherand carried by at least one axial column 14. This formation of thefurnace is characterized by the fact that it is particularly simple andeconomical, that with a practically unchanged low stream resistance, anincreased turbulence of the flue gases and thereby very good heattransfer values and furnace output are obtainable and that also thesound damping effect is extremely good.

In the embodiment shown in FIGS. 4 and 5, the annular channel 4 islimited on the outside by a cylindrically shaped wall 60 and on theinside by a plurality of superimposed cylindrical rings 70. These ringshave a radially outwardly projecting annular collar 80, whereby theannular channel 4 has an open cross section, which cross section has inaxial direction of the furnace alternately narrow points and hollowspace-like widenings and causes thereby, that the flue gases in case ofan axial flow through the annular channel are always alternatelycompressed and accelerated and detensioned and decelerated,respectively, whereby a high heat 7 transfer between the flue gases andthe furnace water is brought about.

The rings 70 consist advantageously of castings, whereby the uppennostrings, in view of a'sufficient heat consistency, are made of a specialcasting, while the lower rings, however, can be made of normally castiron. The rings form an excellent radiation body and due to the shortdistance to the water cooled cylindrical wall 60, they emit a greatquantity of heat by radiation. The formation of the wall limiting theannular channel of superposed rings has the advantage, that the outputof the furnace can be varied within a large range, by superposing moreor less rings, and thereby simultaneously the flue gas temperature canbe adjusted to an optimum to the required values. The rings are equippedwith a collar 90 at one of their edges, which collar 90 interlocks withthe adjacent next ring, whereby the rings are centered relative to eachother. The rings can be connected and joined by anchor screws 100 topackages of, by example, four pieces. Suitably, the rings have at theouter side nose formations 110, with the help of which the entire ringstaple can be centered relative to the cylindrical wall 60. The innerspace of the uppermost ring adjacent to the fireplace is closed up by across-wall 120 of fireproof, ceramic material. This cross-wall 120 locksthe path for the flue gases through the inner space of the rings andforms beyond that a hollow space enclosed by the rings, which is openonly at the bottom to the flue gas outlet and operates as a dampingchamber, which absorbs the pressure oscillations of the flue gases priorto the exit of the flue gases from the furnace. In this connection, theproduction of the rings of castings has the further advantage, that thecomparatively rough sanded surface of the casting rings can absorb flamenoises to a certain extent.

While we have disclosed several embodiments of the present invention, itis to be understood that these embodi ments are given by example onlyand not in a limiting sense.

We claim:

1. A furnace having a vertical substantially cylindrical water boilershell surrounding a fire place for burning of liquid or gaseous fuel bymeans of a burner leading into said fire place, comprising a waterboiler shell,

a burner disposed on a liftable cover arranged on the upper end of saidfurnace and closing a fire place disposed below said cover,

at least one annular channel extending from the end of said fire placeto a flue-gas exhaust disposed at the lower end of said furnace, inorder to feed the flue gases from the lower end of said fire place tosaid flue gas exhaust,

said at least one annular channel being defined on the outside by awater-feeding downward extension of said water boiler shell and on theinside by wall means equipped alternately with annularor screw-likeindentations and projections successively in axial-direction of saidfurnace,

said wall means surrounding a chamber, and

a cross wall at the upper end of said chamber and closing the latter andopen at its lower end pointing towards said flue gas exhaust.

2. The furnace, as set forth in claim 1, wherein said wall meanscomprises a plurality of superposed cylindrically shaped rings, and

said indentations and projections comprise annular collars projectingfrom said rings.

1. A furnace having a vertical substantially cylindrical water boilershell surrounding a fire place for burning of lIquid or gaseous fuel bymeans of a burner leading into said fire place, comprising a waterboiler shell, a burner disposed on a liftable cover arranged on theupper end of said furnace and closing a fire place disposed below saidcover, at least one annular channel extending from the end of said fireplace to a flue-gas exhaust disposed at the lower end of said furnace,in order to feed the flue gases from the lower end of said fire place tosaid flue gas exhaust, said at least one annular channel being definedon the outside by a water-feeding downward extension of said waterboiler shell and on the inside by wall means equipped alternately withannular- or screw-like indentations and projections successively inaxial-direction of said furnace, said wall means surrounding a chamber,and a cross wall at the upper end of said chamber and closing the latterand open at its lower end pointing towards said flue gas exhaust.
 2. Thefurnace, as set forth in claim 1, wherein said wall means comprises aplurality of superposed cylindrically shaped rings, and saidindentations and projections comprise annular collars projecting fromsaid rings.